He took over the charge from Dr T K Alex, the outgoing Director. ISAC is ISRO`s premier centre for conceptualisation, design, fabrication, testing, integration and in-orbit commissioning of satellite systems involving various cutting edge technologies, an ISRO release stated.

Shivakumar began his carrier in ISRO by joining ISRO Telemetry, Tracking and Command Network (ISTRAC) in 1976 at Sriharikota and later served ISAC for two decades during which he made immense contribution to the mission planning, analysis and operations of several Indian satellite missions including Bhaskara, APPLE, IRS and INSAT.

He served as Mission Director for IRS-1B and IRS-1C satellites which successfully completed a decade of operations in orbit. From September 1998 to November 2010, Shivakumar was Director, ISTRAC, which maintains the large constellation of Indian Remote Sensing Satellites in orbit and provides support to satellite launch vehicle missions with a world-wide network of ground stations.

Shivakumar was also the Project Director for realising India`s first indigenous Deep Space Network antenna that measures 32 metres (100 feet) in diameter at Byalalu, near Bangalore. Besides, he played a key role in realising the entire ground segment for Chandrayaan-1 mission including the Indian Space Science Data Centre at Byalalu.

As Associate Director of ISAC since November 2010, he has steered the design and realisation of many communication, remote sensing, navigation and scientific satellites.